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Heats
Nov 17, 2010, 11:59 AM
I'm not familiar with RAID but I don't think it's what I need. I basically want a box that can house 4 or 5 2TB drives full of media that will show up on my desktop as a single external disk for Plex to access. Will a RAID box be able to do this, or is it mostly for backups?



Anonymous Freak
Nov 17, 2010, 12:27 PM
I'm not familiar with RAID but I don't think it's what I need. I basically want a box that can house 4 or 5 2TB drives full of media that will show up on my desktop as a single external disk for Plex to access. Will a RAID box be able to do this, or is it mostly for backups?

RAID really has only three uses:

1. To enable faster access than a single drive is capable of, with not only zero redundancy, but an actual INCREASE in the odds of failure (RAID-0; although nowadays an SSD would be a better option if pure speed is all that matters.) Examples are scratch drives for high-speed-requirement processes like raw HD capture and database logging/index caching. Things where maximum speed is valued over all else, and downtime is acceptable in case of hardware failure.

2. To enable a single logical volume with higher storage capacity than is possible with one physical drive (RAID-0 or RAID-5; RAID-5 adds redundancy in the event of hardware failure.) But, ask yourself, do you REALLY need all of the capacity to show up as one single volume?

3. To provide minimum downtime in the case of hardware failure. Note, I did *NOT* say "to act as a backup". (RAID-1 or its variants, or RAID-5 or its variants.) This is the original purpose of RAID. To provide for redundancy in the event of hardware failure and still have the system stay up and running. For the vast majority of uses, this is overkill. You can live with your HTPC being down for the five hours it takes to replace a hard drive and restore a backup.

In all cases, RAID is *NOT* *NOT* *NOT* a replacement for a true backup solution. If a virus hits you and screws up your data, RAID or not, it's gone. If you get a power spike that kills your computer, it will likely fry one or more of the hard drives in your array, and it's gone.

For an HTPC, the only reasonable RAID use is the "capacity expansion" one. For that, you can get one of the pre-made external RAID units like a LaCie 2big (http://www.lacie.com/products/product.htm?pid=11557), which will appear as one big drive.

Heats
Nov 17, 2010, 01:14 PM
RAID really has only three uses:

1. To enable faster access than a single drive is capable of, with not only zero redundancy, but an actual INCREASE in the odds of failure (RAID-0; although nowadays an SSD would be a better option if pure speed is all that matters.) Examples are scratch drives for high-speed-requirement processes like raw HD capture and database logging/index caching. Things where maximum speed is valued over all else, and downtime is acceptable in case of hardware failure.

2. To enable a single logical volume with higher storage capacity than is possible with one physical drive (RAID-0 or RAID-5; RAID-5 adds redundancy in the event of hardware failure.) But, ask yourself, do you REALLY need all of the capacity to show up as one single volume?

3. To provide minimum downtime in the case of hardware failure. Note, I did *NOT* say "to act as a backup". (RAID-1 or its variants, or RAID-5 or its variants.) This is the original purpose of RAID. To provide for redundancy in the event of hardware failure and still have the system stay up and running. For the vast majority of uses, this is overkill. You can live with your HTPC being down for the five hours it takes to replace a hard drive and restore a backup.

In all cases, RAID is *NOT* *NOT* *NOT* a replacement for a true backup solution. If a virus hits you and screws up your data, RAID or not, it's gone. If you get a power spike that kills your computer, it will likely fry one or more of the hard drives in your array, and it's gone.

For an HTPC, the only reasonable RAID use is the "capacity expansion" one. For that, you can get one of the pre-made external RAID units like a LaCie 2big (http://www.lacie.com/products/product.htm?pid=11557), which will appear as one big drive.

Thanks for your input. So I'm not really worried about backing up the data, and having it show as one drive on my HTPC isn't the end of the world, so again my question is, would a RAID box be useful to me to house 4 or 5 HD's for storage? Ideally I would like these to be connected to another computer on my network away from the tv.

From A Buick 8
Nov 17, 2010, 01:54 PM
Thanks for your input. So I'm not really worried about backing up the data, and having it show as one drive on my HTPC isn't the end of the world, so again my question is, would a RAID box be useful to me to house 4 or 5 HD's for storage? Ideally I would like these to be connected to another computer on my network away from the tv.

i am not saying what i am doing is the way to go, but i am using N-RAID (Non-RAID).

I have two 2TB drives in an OWC enclosure and mounts on my desktop as 1 4TB drive.

zhenya
Nov 17, 2010, 01:56 PM
Thanks for your input. So I'm not really worried about backing up the data, and having it show as one drive on my HTPC isn't the end of the world, so again my question is, would a RAID box be useful to me to house 4 or 5 HD's for storage? Ideally I would like these to be connected to another computer on my network away from the tv.

Yes. What you are looking for is called Network Attached Storage. There are literally thousands of devices that fit your needs. I'd suggest you look at Synology, Qnap, Windows Home Server, and Drobo for a start.

ActionableMango
Nov 17, 2010, 05:24 PM
You either want a 4- or 5-drive external enclosure that supports JBOD, or you can use OS X to software RAID JBOD from a number of connected drives.

Here are instructions for software RAID JBOD in OS X:
http://macs.about.com/od/usingyourmac/ss/raidjbod.htm

Eclipse278
Nov 17, 2010, 06:58 PM
unRAID sounds like the best bet for what you want:

http://revision3.com/systm/unraid

unRAID is similar to RAID 5 in that you can make a big virtual drive out of many disks, and if one disk fails you can rebuild the data so it's not lost. Where it's better than RAID 5 is that you can mix and match different size disks. So whenever you get a new HDD you can add it to the block or replace the smallest drive and it'll rebuild and run like a champ forever. Where it's worse than RAID 5 is there's no striping so it's slower than RAID 5, but still definitely fast enough for HTPC streaming.

JBOD sucks because if one disk fails you'll lose all the data on all the disks.

And like Anonymous Freak says, JBOD, RAID5, or unRAID are not backup solutions so a virus or accidental file deletion command can be devastating.

emaja
Nov 17, 2010, 11:21 PM
I use the mini storage tower from Addonics found here (http://www.addonics.com/products/raid_system/mst4.asp) with their AD4SR5HPMU-E (http://www.addonics.com/products/host_controller/ad4sr5hpmus.asp) eSATA/USB controller. It allows me to select different RAID levels to balance volume size and redundancy against drive failure. I know it is not a backup solution, but it is a good solution to fit a lot of storage in a small, expandable package.

I started with 3, 320 GB drives and now have 4, 1 TB drives in there and that gives me 3 GB total storage with a parity drive. Any single drive can fail and I can replace it without losing any data.

It mounts on my Mac Book Pro's desktop like a USB drive and I can easily stream to my 2 ATVs connected wirelessly without any stuttering.

There are other solutions out there, but this one works for me and was only $180-ish plus the drives. I am very happy with it.